1. Field of the Invention
The invention generally pertains to hand held powered woodworking tools and specifically to tools for edge joining boards.
2. Description of Related Art
Plate joiners and dowel jigs are today's standard tools for edge joining boards. Plate joiners have radially cutting tools that cut a semicircular slit in the edge of each board to be joined. A round disk, referred to as a biscuit is inserted in the slits and serves to roughly align the boards being joined.
Plate joiners have their disadvantages. The worst is their tendency to kick sideways as the radially cutting edge of the tool touches the wood. This not only produces a poorly aligned joint but it's also dangerous. A second drawback is that with a radially cutting tool, the length of the slit becomes relatively long in order to get adequate slit depth. A long slit means the edge being joined must also be long. This becomes a real problem when joining pieces with narrow edges, such as those found in cabinet frames and chair tendons. A third problem is that the radially cutting tool is of a fixed size limiting its versatility in joining boards of various thicknesses. The "one size fits all" philosophy forces compromises rather than optimizing the joint design. A further disadvantage is that the cutting tool is coupled to its drive shaft at a location inside the housing. This makes it extremely difficult to remove the cutting tool for resharpening.
The other commonly used tool, a doweling jig, involves clamping a drill bushing to the boards being joined. The bushing serves as a guide for a conventional drill bit. Dowel jigs are time consuming to use and can leave clamp indentations in the wood.